class Game_Party < Game_Unit
  def max_item_number(item)
    return 999 unless item.uniq_item?

    1
  end
end

class Window_ItemList < Window_Selectable
    def draw_item_number(rect, item)
        draw_text(rect, sprintf(":%3d", $game_party.item_number(item)), 2)
    end
end